Name
BackhandSelfRedirect
Synopsis
BackhandSelfRedirect <On|Off> Default Off Directory
A common way to run Apache when heavily loaded is to have two
instances of Apache running on the same server: one serving static
content and doing load balancing and the second running CGIs,
typically with mod_perl
or some other built-in
scripting module. The reason you do this is that each instance of
Apache with mod_perl
tends to consume a lot of
memory, so you only want them to run when they need to. So, normally
one sets them up on a different IP address and carefully arranges
only the CGI URLs to go to that server (or uses
mod_proxy
to reverse proxy some URLs to that
server). If you are running mod_backhand
, though,
you can allow it to redirect to another server on the same host. If
BackhandSelfRedirect
is off
and
the candidacy functions indicate that the host itself is the best
candidate, then mod_backhand
will simply
“fall through” and allow the rest
of Apache to handle the request. However, if
BackhandSelfRedirect
is on
,
then it will redirect to itself as if it were another host, thus
invoking the “heavyweight”
instance. Note that this requires you to set up the
MulticastStats
directive to use the interface the
mod_perl
(or whatever) instance to which
it’s bound, rather than the one to which the
“lightweight” instance is bound.
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